Blade sharpening device for rotatable chopping cylinders

ABSTRACT

A blade sharpening device for use on a rotatable chopping cylinder of a forage harvester or the like, which cylinder has a plurality of circumferentially spaced and generally parallel blades that are of a generally spiral shape. The device includes a carriage that moves along parallel to the cylinder and has a sharpening tool extending from it for contact with the blades, and guide means connected directly to the carriage for guiding abutment with a succeeding blade whereby as the carriage moves along the axis of the cylinder, the guide means abutting against the succeeding blades insures that the sharpening tool is at all times properly orientated to the blade being sharpened.

Leverenz 51 Apr. 3, 1973 [54] BLADE SHARPENING DEVICE FOR ROTATABLECHOPPING CYLINDERS [75] Inventor: John H. Leverenz, West Bend, Wis.

[73] Assignee: Gehl Company, West Bend, Wis.

[22] Filed: June 11, 1971 [21] Appl. No.: 152,206

Primary Examiner-James L. Jones, Jr. Attorney-James Nilles [57] ABSTRACTA blade sharpening device for use on a rotatable chopping cylinder of aforage harvester or the like, which cylinder has a plurality ofcircumferentially spaced and generally parallel blades that are of agenerally spiral shape. The device includes a carriage that moves alongparallel to the cylinder and has a sharpening tool extending from it forcontact with the blades, and guide means connected directly to thecarriage for guiding abutment with a succeeding blade whereby as thecarriage moves along the axis of the cylinder, the guide means abuttingagainst the succeeding blades insures that the sharpening tool is at alltimes properly orientated to the blade being sharpened.

7 Claims, 4 Drawing Figures PATENTEDAPRZ? 1975 3,724,139

SHEET 1 OF 4 INVENTOR= JOHN H. LEVERENZ ATTORNEY PATENTEDAPR 3 I975SHEET 2 OF 4 INVENTOR JOHN H. LEVERENZ BY= zjf 'e ATTORNEY PATENTEU R 3I935 SHEET 3 [1F 4 INVENTOR= JOHN H. LEVERENZ BY= ATTORNEY T "ti J| KOLO PATENTEUAPR 3 ms SHEET U 0F 4 R O T N E V m JOHN H. LEVERENZ ATTORNEYBLADE SIIARPENING DEVICE FOR ROTATABLE CHOPPING CYLINDERS BACKGROUND OFTHE INVENTION This invention pertains to sharpening devices forsharpening the blades of a cylindrical rotor of a forage harvester orthe like and without the necessity of removing the knives from theharvester.

Prior art devices of this general type have been proposed and used witha certain degree of success. However, they had certain shortcomingsbecause of their complex nature, and amount of time required to set themup for use and then disconnecting them after use, and the inability ofsome of these devices to maintain the blade being sharpened in properorientation to the sharpening tool.

An example of a prior art sharpening device is shown in the US. Pat. No.3,479,776, issued Nov. 25, 1969 to Berg and entitled Blade Sharpener.That particular prior art device utilized a lever extending generallyradially from the cylinder and then interconnected by a complicatedlinkage mechanism to the axially movable carriage, and that particulardevice also utilized guide means which moved along the cutting or anglededge of the succeeding blade in order to guide the sharpening tool as itmoved along the particular blade to be sharpened.

SUMMARY OF THE INVENTION The present invention provides a bladesharpening device for a rotatable chopping cylinder of a forageharvester or the like, and which cylinder has a series ofcircumferentially spaced and generally parallel blades that are of agenerally spiral shape. The device includes a carriage that movesparallel to the axis of the cylinder and has a sharpening tool forengagement with one of the blades as it moves longitudinally of thecylinder. A guide means is carried directly and rigidly supported by thecarriage and has a guiding element that contacts the succeeding bladeand thereby guides the sharpening tool in an exact manner over the bladeto be sharpened. In this manner, all blades are sharpened preciselyalike and the sharpening operation is guided by the shape of the bladesthemselves. The invention also provides a spring loaded means which actsagainst the cylinder and insures that the succeeding blade which is usedfor guiding purposes is held firmly against the guide means at all timesduring the sharpening operation. Still another aspect of the inventionrelates to means for manually shifting the reciprocating carriage alongthe guide track means and with a continuous cranking motion by theoperator. Still another aspect relates to means for quickly andaccurately changing the angle disposition of the sharpening toolrelative to the blade being sharpened so that the desired bevel ismaintained on the cutting edge of the blade.

These and other objects and advantages of the present invention willappear hereinafter as this disclosure progresses, reference being had tothe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of aportion of a forage harvester embodying the present invention showingcertain parts being swung away from their normal operating position andother parts being shown as broken away or removed for the sake ofclarity in the drawings;

FIG. 2 is an end elevational view of the device shown in FIG. 1, but onan enlarged scale and showing certain parts being broken away or removedfor the sake of clarity, and showing the grinder carriage in theposition when it commences its sharpening travel at one end of theknife;

FIG. 3 is a view taken generally along the line 3-3 in FIG. 2, certainparts being shown as broken away for the sake of clarity, and showingthe carriage at one extreme end of its travel, before contact with aknife to be sharpened; and

FIG. 4 is a sectional, plan view taken generally along the line 4-4 inFIG. 2, but showing the carriage when about half-way through asharpening pass over the knife, certain parts being shown as broken awayor removed for the sake of clarity.

DESCRIPTION OF A PREFERRED EMBODIMENT The general organization of theinvention as applied to a forage harvester is shown in FIG. 1, theforage harvester including a housing H supported on ground engagingmeans such as the wheel means W, a blower B attachable to the housingfor receiving the cut crop from the housing via the blower opening 1.The blower includes a fan F rotatably mounted therein which delivers thecut crop to the tangentially extending chute C in the known manner. Theblower B has been shown for purposes of clarity as being swung to therear of the housing, but it will be understood that in operation, theblower B will be swung snugly against the housing so that the opening 1is in immediate adjacency with the housing for receiving cut cropstherefrom. Furthermore, when the machine is operating in the field,another cover (not shown) would enclose the top of the chopping cylinder5, to be described.

The housing also has a top cover 2 which is pivoted at 3 to the housingand which can be swung to the open position shown in FIG. 1 or to arearward position in which it covers the sharpening device, now to bedescribed, when the latter is not in operation.

The conventional chopping cylinder 5 is rotatably mounted in the housingand rotation in the direction indicated by the curvilinear arrow in FIG.4. The cylinder has a series, for example six shown, of blades ll, 12,13, 14, 1S and 16 which are circumferentially spaced and generallyparallel to one another, and are mounted on the cylinder rotor frame 18.These conventional blades are arranged to define the periphery of thecylinder and are generally spiral in form. The blades include a frontsharpening edge defined by the respective bevelled portions, for example11a of the blade 11 which is shown in the position for being sharpened.These edges must be reground periodically to insure sharpness of theblade. The cylinder also includes a plate-like member 20 rigidly fixedto the outer'end of the cylinder shaft 21 and located on the outside ofthe housing II. This plate-like member has a series of projections 22arranged around its periphery, one for each of the blades. As shown inFIGS. 1 and 2, spring loaded means 25 are provided to act between thehousing II and the plate-like member so as to bias the cylinder in thedirection of rotation indicated by the curvilinear arrow in FIG. 2. Morespecifically, the spring loaded means 25 includes an extensible strut 26which is pivoted at 27 to the housing and whichhas a clevice 28 fixed bya bolt means 29 to the other end of the extensible strut 26. A spring 30acts between an anchor 31 on the strut and the extensible end 32 of thestrut to thereby urge the bolt means into firm contact with theprojections 22 and consequently bias the cylinder in the direction ofrotation noted, for a purpose that will hereinafter appear.

Guide track means in the form of a pair of parallel rods 40 and 41 aremounted on the housing and are arranged in parallelism with the cylinderaxis and adjacent the top opening 42 in the housing. One of said rods ismounted on each side of the housing and extend generally coextensivelyin length therewith.

Carriage 50 is slideably mounted on each of the guide rods 40 and 41 sothat the carriage can be slid from the end of cylinder to the other,more specifically across the full length of the cylinder 5. A sharpeningtool in the form of a rotatable grinding wheel 52 extends from theelectric motor 53 so that the latter can drive the wheel 52 through itsdrive shaft 54. The motor in turn is rigidly carried on the carriage bybracket 55 which is connected by an adjustable pair of arms 56 pivotedat 57 to the carriage proper. The other end of the arms 56 arethreadably engaged with a crank 59 rotatably mounted in the bifurcatedbracket 55. In this manner, adjustment of the crank 59 changes theheight of the motor and the grinding wheel relative to the cylinder. Thearms 56 are also connected by a link 62 which is pivoted at one end tothe arms 56 at 63 and then connected at its other end to an eccentric 64rotatably journalled and adjustably mounted in the carriage 50. Therebyadjustment of the eccentric 64 varies the angle of the motor 53 and itsgrinding wheel relative to the blade to insure that the desired angle isground for the bevel edge 11a.

Guide means 70 are provided for insuring that the cylinder rotates theproper amount as the carriage moves axially thereover, so that thegrinding wheel is at all times properly positioned in respect to theblade 11 being sharpened and that the proper edge is formed on theblade. This guide means includes an arm 71 which is rigidly fastened bybolts 73 to the carriage proper, which arm extends rearwardly from thegrinding wheel 52. The guide means includes a shaft 74 which isthreadably adjustable on the end of the arm and which carries a pair ofrollers 76 at its lower end. The rollers are adapted to roll along theinner side 77 of that blade 16 which succeeds the blade 11 beingsharpened. A pair of rollers are used to insure that at least one rolleris in guiding contact with the guiding blade until the grinding wheelpasses completely over the entire length of the blade. The guide meansalso includes a shoe 78 having a curved or angled leading edge 79 sothat when the carriage is at one extreme end of the cylinder and theguide means is about to make contact with the corresponding end of blade16, the guide means will make proper contact with the blade 16 toproperly orientate the guide means and carriage in respect to thecylinder prior to the sharpening pass of the wheel 52 over the blade.

The spring loaded means 25 is provided for biasing the cylinder in thedirection of rotation indicated in FIG. 2 by the curvilinear arrow aspreviously mentioned. In this manner, the blade 16 is held snuglyagainst the rollers 76 of the guide means as the sharpening tool 52moves axially along the cylinder. In other words, as the sharpeningwheel 52 moves along the length of the cylinder to sharpen the blade 11,the cylinder must also rotate sufficiently, because of the spiral natureof the blade shape, to insure that the wheel 52 is presented at theproper attitude to the blade along its entire length.

The guide means can be shifted generally vertically on the arm 71 bymeans of the threaded nature of its rod 74 and the lock nuts 81 whichcan hold the rod 74 in any adjusted position relative to the arm 71.

Manually operated drive means are provided for driving the carriage 50along the length of the guide track means 40, 41 in the eitherdirection. This drive means includes a crank which can be continuouslyrotated by the operator so as to reciprocate the carriage along theguide track means. More specifically, the crank has a relatively smallsprocket 92 fixed thereto and over which the endless chain 93 istrained. A shaft 94 is fixed within the housing and has a pair ofsprockets 95 and 96 fixed thereto. Chain 93 is trained over sprocket 95while another endless flexible member in the form of a roller chain 97is trained around sprocket 96. Another shaft 98 is also mounted in thehousing and has a sprocket 99 mounted thereon and over which the chain97 is also trained.

A drive chain pin 100 is carried by the chain 97 and extends from theside thereof, a plate member 101 is fixed to the carriage and has avertical slot 102 formed therein for the reception of the chain pin 100.Thus the pin 100 travels in an orbital path with the chain 97 when theoperator turns the crank 90. The pin 100 con sequently carries thecarriage with it via the connecting slotted plate 101. At either end oftravel of the carriage, the pin moves vertically in the slot 102 andcontinued rotation of the crank 90 then causes the pin to reverse itstravel, carrying with it the carriage. As a result, continuousrotational motion of the crank 90 by the operator in one direction istranslated into reciprocating motion of the carriage. Thus the grindingwheel 52 can be caused to make various passes, in either direction, overthe blade being sharpened.

I claim:

1. A blade sharpening device for use with a forage harvester thatharvests and delivers crops to a housing having a top opening, and acutting cylinder rotatably retained within the housing and adjacent saidtop opening, the cylinder being composed of a plurality ofcircumferentially spaced and substantially parallel, peripheral andspiral shaped cutting blades supported on a cylinder frame, thesharpening device comprising: guide track means supported on saidhousing and dispositioned parallel to the cylinder axis, a movablecarriage supported on said track means for movement parallel to thecylinder axis, a blade grinding wheel on the carriage and having a flatgrinding surface engageable with a cylinder blade to be sharpened, aguide means rigidly secured to said carriage and spaced from saidsharpening tool and including roller means for guiding engagement alongand directly against an inner side of another cylinder blade which iscircumferentially spaced from said blade to be sharpened, whereby assaid carriage moves along said track means said guide means moves alongand is guided by said another blade to maintain said sharpening tool inproper sharpening attitude relative to the blade to be' sharpened.

2. The sharpening device set forth in claim 1 including a spring loadedmeans connected between said housing and an axially extending portion ofsaid cylinder for urging the latter in a direction of rotation wherebysaid another blade is held firmly against said guide means as saidcarriage moves along said track means in sharpening said blade.

3. The device of claim 2 further characterized in that said extendingportion of said cylinder comprises a plate-like member located at oneend of said cylinder and on the outer side of said housing and having aengagable series of projections selectively engagable by said springloaded means whereby said cylinder is biased in one direction ofrotation by said spring loaded means.

4. A device as set forth in claim 1 including a manually operated drivemeans connected to said carriage for moving the latter along said guidetrack means.

5. The device as set forth in claim 4 further characterized in that saidmanually operated drive means comprises an endless flexible member,means for rotating said endless flexible member, and a pin and slotconnection between said carriage and said endless flexible memberwhereby as the latter travels in its path, said carriage is reciprocatedalong said guide track means.

6. The device as set forth in claim 1 further including manuallyadjustable means for angularly positioning said wheel with respect tothe blades.

7. The device as set forth in claim 1 further characterized in that saidguide means comprises a guide shoe having an inclined leading edge foraligning said guide means initially with said blade.

1. A blade sharpening device for use with a forage harvester thatharvests and delivers crops to a housing having a top opening, and acutting cylinder rotatably retained within the housing and adjacent saidtop opening, the cylinder being composed of a plurality ofcircumferentially spaced and substantially parallel, peripheral andspiral shaped cutting blades supported on a cylinder frame, thesharpening device comprising: guide track means supported on saidhousing and dispositioned parallel to the cylinder axis, a movablecarriage supported on said track means for movement parallel to thecylinder axis, a blade grinding wheel on the carriage and having a flatgrinding surface engageable with a cylinder blade to be sharpened, aguide means rigidly secured to said carriage and spaced from saidsharpening tool and including roller means for guiding engagement alongand directly against an inner side of another cylinder blade which iscircumferentially spaced from said blade to be sharpened, whereby assaid carriage moves along said track means said guide means moves alongand is guided by said another blade to maintain said sharpening tool inproper sharpening attitude relative to the blade to be sharpened.
 2. Thesharpening device set forth in claim 1 including a spring loaded meansconnected between said housing and an axially extending portion of saidcylinder for urging the latter in a direction of rotation whereby saidanother blade is held firmly against said guide means as said carriagemoves along said track means in sharpening said blade.
 3. The device ofclaim 2 further characterized in that said extending portion of saidcylinder comprises a plate-like member located at one end of saidcylinder and on the outer side of said housing and having a engagableseries of projections selectively engagable by said spring loaded meanswhereby said cylinder is biased in one direction of rotation by saidspring loaded means.
 4. A device as set forth in claim 1 including amanually operated drive means connected to said carriage for moving thelatter along said guide track means.
 5. The device as set forth in claim4 further characterized in that said manually operated drive meanscomprises an endless flexible member, means for rotating said endlessflexible member, and a pin and slot connection between said carriage andsaid endless flexible member whereby as the latter travels in its path,said carriage is reciprocated along said guide track means.
 6. Thedevice as set forth in claim 1 further including manually adjustablemeans for angularly positioning said wheel with respecT to the blades.7. The device as set forth in claim 1 further characterized in that saidguide means comprises a guide shoe having an inclined leading edge foraligning said guide means initially with said blade.